The Montgomery County Fire Marshal's Office is trying to determine what sparked a fire that destroyed a $1 million home in The Woodlands early Friday.

Flames were spreading throughout the home on Rhapsody Bend Drive when firefighters arrived from The Woodlands Fire Department about 8:15 a.m., investigators said.

The stubborn blaze quickly grew, forcing firefighters to take up a defensive posture and fight the fire from outside, said Capt. David Parker of The Woodlands Fire Department. Shortly afterward, the concrete slate roof began to collapse in some spots, sending down tiles that weigh about 10 pounds each, he said.

About 8:45 a.m., firefighters requested assistance from South Montgomery County, Magnolia and Needham Road, and paramedics from the Montgomery County Hospital District. No injuries were reported.

Parker estimated damage to the home and its contents at about $1 million.